[Spice-devel] [Qemu-devel] seamless migration with spice

[Alon Levy]

On Mon, Mar 12, 2012 at 11:26:50AM +0100, Gerd Hoffmann wrote:
>   Hi,
> 
> >>> As for certain other
> >>> data, such
> >>> as (but not limited to) partially parsed agent messages, these should be
> >>> send through the regular vmstate methods IMHO.
> >>
> >> That isn't easy to handle via vmstate, at least as soon as this goes
> >> beyond a fixed number of fields aka 'migrate over this struct for me'.
> >> Think multiple spice clients connected at the same time.
> > 
> > Migrate this struct n times for me.
> 
> I think for the agent case this isn't needed.  Or is every client
> allowed to speak to the agent in case of multiple clients connected?  I
> somehow doubt this can work as the agent protocol can't multicast ...
> 

Actually the agent protocol does extend nicely to multiple clients - I
forgot the name but there is an additional wrapper between the
client/server originating message and the guest received message, that
is currently used for server or client originating messages, and can be
reused to have multiple in flight different client messages. We don't
use it for guest generated messages, but we could as well. Multicast
would be another number.

> cheers,
>   Gerd
> 
>